In a face milling process, burrs may be formed at a corner portion of a machined surface (a corner portion formed between an end surface of a workpiece toward which the workpiece is cut through and the machined surface) during the process. Known technologies provided with a deburring function include, for example, a rotary cutting tool disclosed by PTL 1 listed below.
The rotary cutting tool disclosed by PTL 1 includes, in addition to a major cutting insert that is responsible for major cutting, a so-called circular cutting insert having a circular cutting edge. Burrs, if formed, are removed by the circular cutting insert.